I've done all of the above and nothing has changed; I relogged and nothing happened.
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HugoMay 24 '11 at 14:07

Hmm...try checking in the ATI Catalyst Control Center. Open that up, go to 3D, then "More Settings". Under "Wait for Vertical refresh", drag the slider all the way to the left.
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JoshMay 24 '11 at 14:19